Sunday, May 13, 2007


Polyunsaturated fat is in fact more likely to kill you than saturated fat is. See the evidence reviewed below

That diet might play a part as a cause of CHD was hypothesised by another American doctor, Ancel Keys, in 1953. Using data from seven countries in his 'Seven Countries Study', Keys compared the death rates from CHD and the amounts of fats eaten in those countries to demonstrate that heart disease mortality was higher in the countries that consumed more fat than it was in those countries that consumed less. (At that time, data from many more countries were available. It seems that Keys ignored the data from those that did not support his hypothesis.) And so the 'diet/heart' hypothesis was born.

But how do we know it is true? It is all very well having a theory, what you have to do then is prove it. In medicine, the usual way is to select two groups of people, as identical for sex, age, and lifestyle as possible. One group called the control group, carries on as normal while the other, called the intervention group, tries the new diet, drug or whatever. After a suitable time, the two groups are compared and differences noted.

Keys' fat-diet/heart disease hypothesis was persuasive so, to test it, several large-scale, long-term, human intervention studies were set up in many parts of the world. These involved hundreds of thousands of subjects and hundreds of doctors and scientists and cost billions of dollars in an attempt to prove that a fatty diet caused heart disease.

Framingham Heart Study

The most influential and respected investigation of the causes of heart disease is the Framingham Heart Study. This study was set up in the town of Framingham, Massachusetts, by Harvard University Medical School in 1948 and is still going on today. It was this study that gave rise to the dietary 'risk factors' with which we all are so familiar today. The Framingham researchers thought that they knew exactly why some people had more cholesterol than others - they ate more in their diet. To prove the link, they measured cholesterol intake and compared it with blood cholesterol. Although subjects consumed cholesterol over a wide range, there was little or no difference in the levels of cholesterol in their blood and, thus, no relationship between the amount of cholesterol eaten and levels of blood cholesterol was found. (Although it is interesting that women who had the highest levels of cholesterol in their blood were ones who had eaten the least cholesterol.)

Next, the scientists studied intakes of saturated fats but again they could find no relation. There was still no relation when they studied total calorie intake. They then considered the possibility that something was masking the effects of diet, but no other factor made the slightest difference. After twenty-two years of research, the researchers concluded:

"There is, in short, no suggestion of any relation between diet and the subsequent development of CHD in the study group."

On Christmas Eve, 1997, after a further twenty-seven years, the Journal of the American Medical Association (JAMA) carried a follow-up report that showed that dietary saturated fat reduced strokes. As these tend to affect older men than CHD, they wondered if a fatty diet was causing those in the trial to die of CHD before they had a stroke. But the researchers discount this, saying:

"This hypothesis, however, depends on the presence of a strong direct association of fat intake with coronary heart disease. Since we found no such association, competing mortality from coronary heart disease is very unlikely to explain our results."

In other words, after forty-nine years of research, they are still saying that they can find no relation between a fatty diet and heart disease.

Multiple Risk Factor Intervention Trial

One of the largest and most demanding medical studies ever performed on humans, The Multiple Risk Factor Intervention Trial (known in the medical world, by its initials, as MR. FIT) involved 28 medical centers and 250 researchers and cost $115,000,000. The researchers screened 361,662 men and deliberately chose subjects who were at very high risk to ensure that they achieved a statistically significant result. They cut cholesterol consumption by forty-two percent, saturated fat consumption by twenty-eight percent and total calories by twenty-one percent. Yet even then they didn't succeed. Blood cholesterol levels did fall, but by only a modest amount and, more importantly, coronary heart disease was unaffected. Its originators refer to the results as "disappointing" and say in their conclusions:

"The overall results do not show a beneficial effect on Coronary Heart Disease or total mortality from this multifactor intervention."

The Tecumseh Study

The Tecumseh Study attempted to correlate blood cholesterol levels measured one day with the amounts of fats eaten the previous day - but found none. Interestingly, It was demonstrated that people who ate the least cholesterol had the highest levels of blood cholesterol. Although not looking for it, this study also found that blood cholesterol levels were quite independent of whether the dietary fats were saturated or unsaturated. Thus another 'diet-heart' hypothesis, that only saturated fats are to blame, was invalidated.

WHO European Coronary Prevention Study

The results of the World Health Organisation's European Coronary Prevention Study were called "depressing" because once again no correlation between fats and heart disease was found. They had cut saturated fats down to only eight percent of calorie intake daily, yet in the UK section there were more deaths in the intervention group than in the control group.

The North Karelia Project

North Karelia, which had Finland's highest rates of heart disease, was compared with neighbouring Kuopio in The North Karelia Project. In North Karelia, risk factors were cut by seventeen percent over the period of the study. In North Karelia there was a reduction in both CHD mortality and total mortality. Also this study shows, however, that in Kuopio, the control group, where there were no restrictions, there was an even bigger decline in both CHD and total mortality. These studies suggest that adopting a 'healthy' lifestyle may actually have inhibited the decline in heart disease. They certainly give it no support.

This paper does not allow me to go through the more minor studies but they all show little convincing correlation between either the amount of fat eaten and heart disease or the type of fat eaten and heart disease. A review of twenty-six studies published in 1992 concluded that:

"Lowering serum cholesterol concentrations does not reduce mortality and is unlikely to prevent coronary heart disease. Claims of the opposite are based on preferential citation of supportive trials."

One that seemed to support the 'healthy' recommendations was a Finnish trial published in 1975. In the five years that the trial ran, cholesterol levels were lowered significantly, and the study was hailed as a success. But in December 1991 the results of a 10-year follow-up to that trial found that those people who continued to follow the carefully controlled, cholesterol-lowering diet were twice as likely to die of heart disease as those who didn't - some success! Professor Michael Oliver, writing in the British Medical Journal commenting on the results, writes

"As multiple intervention against risk factors for coronary heart disease in middle aged men at only moderate risk seem to have failed to reduce both morbidity and mortality such interventions become increasingly difficult to justify. This runs counter to the recommendations of many national and international advisory bodies which must now take the recent findings from Finland into consideration. Not to do so may be ethically unacceptable."

Despite this wealth of evidence, nutritionists and the media continue to mislead us. They tell us, for example, that the recent fall in the numbers of heart deaths in the USA is because Americans are eating less fat. The graph below, however, shows clearly that while CHD in the USA peaked in the 1950s and has fallen consistently since, this is against a background of rising fat intake.

It is difficult to understand how the fat hypothesis gained such credibility in the USA as its history more than most does not support it. The North American continent had been opened up by explorers and trappers who lived, very healthily, as did the Amerindians, almost entirely on fresh meat and pemmican. As real pemmican is half dried lean meat and half rendered animal fat, and as fat has over twice the calorific value of protein, more than seventy percent of the energy in their diet came from fat.

Dieticians also say that the British had less CHD in the 1940s when fat was rationed. However, the decade of rationing went on into the early 1950s with fat being the last food to come off ration in 1954. Again the graph shows clearly that the most rapid rise in CHD occurred during that period. Also, during the period of rationing, British farmers had a very low incidence of heart disease when one would have expected their intake of fats, particularly animal fats, to have been higher than most.

Experience in other countries

Keys based his fat-causes-heart disease hypothesis on a comparison between countries. When we are told that we are 'the sick man of Europe', we are also compared to other countries. So lets do a similar comparison.

1. In Japan, intakes of animal fat have more than doubled since the end of the Second World War. Over the same period their incidence of coronary heart disease has fallen consistently. In Israel too an increased consumption of saturated fats was followed by a fall in coronary deaths.

2. The dietary changes in Sweden parallel those in the USA, yet heart disease mortality in Sweden was rising while American rates were falling.

3. There is also a threefold variation in rates of heart disease between France and Finland even though fat intake in those two countries is very similar.

4. Among south Asians in Britain there is an unusually high incidence of heart disease, yet living on largely vegetarian diets, they have low levels of blood cholesterol and eat diets that are low in saturated fat.

5. Indians in South Africa have probably the highest rates of coronary disease in the world yet there is no apparent reason why they should based on the current dietary hypotheses.

6. Until recently, Indians in India had a very low incidence of heart disease while using ghee (clarified butter), coconut oil and mustard seed oil - all of which are highly saturated. The epidemic of heart disease in India began only after these were replaced with peanut, safflower, sunflower, sesame and soybean oils, all of which are high in polyunsaturated oils.

7. Lastly, the World Health Organization is apparently in ignorance of epidemiological data that do not support its recommendation to reduce dietary saturated fat. While it talks of coronary heart disease being responsible for most deaths in Caribbean countries, fat intake there is remarkably low.

Polyunsaturated fats

The arguments for the polyunsaturated fat hypothesis are no more convincing than those for the cholesterol theory. The claim is that unsaturated fats have a protective or preventative effect on CHD. But in Israel, when consumption of polyunsaturated fats was about twice that of most Western countries, there was a very high incidence of CHD. Those given high polyunsaturated diets in a trial in New South Wales fared significantly worse than those on a free diet. And this is the finding in most trials that have increased the ratio of polyunsaturated fats.

From as early as 1971, an excess of cancer deaths has been reported in trials using diets that were high in polyunsaturated fats. Polyunsaturated fats are also blamed for a doubling in the incidence of gallstones in the general public.

One of the pioneers of the polyunsaturated-fat-prevents-CHD hypothesis was the American cardiologist E. H. Ahrens Jr.. After twenty-five years of further research, however, he concluded that it was "irresponsible" to continue to press the polyunsaturated fat recommendations on the general public. He went on:

"If the public's diet is going to be decided by popularity polls and with diminishing regard for the scientific evidence, I fear that future generations will be left in ignorance of the real merits, as well as the possible faults in any dietary regimen aimed at prevention of coronary heart disease."

Another of the original proponents of the low-fat, low-cholesterol hypothesis, and a member of the Norwegian Council for Diseases of the Heart and Arteries, Professor Jens Dedichen of Oslo, also changed his mind. In the 1950s Norway launched a cholesterol-lowering regimen in which soy margarine, that is high in polyunsaturated fatty acids, replaced butter, and soy oil was used extensively. During the subsequent 20 years the increase in the use of soy-based products was accompanied by a steep and continuing rise in deaths from coronary thrombosis. Professor Dedichen drew attention to the failure of the programme - and received a very hostile reaction from his colleagues.

Also castigated were members of the National Academy of Sciences and the National Research Council of America when in a report of May 1980, they stated that prevention of heart disease could not be achieved by reducing blood cholesterol using either diet or drugs, and said that such measures should be abandoned.

More here


I originally wrote a version of this post for my Greenie Watch blog but it is relevant here too

Ever since I first started doing research into environmentalism over 30 years ago, it has seemed obvious to me that they are simply a revival of mankind's most primitive religion -- nature worship. Awe before nature is in fact probably so primitive and goes back so far that it has to an extent been hardwired into us.

But many religions are extremely destructive of human welfare -- with Islam being a rather obvious example -- and the plainly misanthropic (people-hating) nature of environmentalism was obviously always going to be a big problem. That problem was for many years obvious in only minor ways. An outright people-hating message was obviously never going to gain much traction so Greenies had to present their demands for change under the old Leftist label: "It is for your own good". And convincing people that something is for your own good when it is actually bad for you is a hard sell. As a result, the nature-worshippers DID inadvertently do us some good in that some of the things they pushed for -- such as cleaner air and water -- really were good for us.

Of late, however, Greenies have really hit the jackpot. They have finally found something that is REALLY bad for us that they can push to the credulous as being good for them. I refer, of course to the global warming craze. It has for some time seemed to me that the vast economic destruction that this craze has already got underway establishes environmentalism as a really evil religion.

But, while there is no doubt that environmentalism is a misanthropic religion, I have come to doubt that that the environmentalists are really most to blame for their excesses. I think there is another force at work which is doing most of the damage. And it is the same force that underlies most Leftism: Excess ego. But it is not ego in politics that is the problem. It is ego in science. It is dishonest science that gives the global warming scare its legs. The average Greenie is just part of a Greek chorus in the background.

But am I not being absurd? How can I say that scientists are on a large scale ego-filled to the point of dishonesty? And how does ego come into science?

Let me initially make clear what I am saying: I am saying that scientists pump up the global warming scare not because they are subscribers to the Greenie religion (though they may well be) but because it inflates their egos. And the clearest proof that ego inflation is a hugely distorting influence on science comes from an area of science that has very little to do with environmentalism and which is arguably the most respected area of scientific research: The medical literature.

So am I now REALLY descending into absurdity? I wish I was. If we cannot trust the academic literature of medicine for an objective view of reality, whom can we trust? I will not attempt to answer that question but I do want to point out that it is crystal clear that we CANNOT trust the academic medical literature. Anyone who knows anything about that literature will know how subject to fashion it is and how what is proclaimed as bad for you in one era is in a later era proclaimed as good for you (e.g. alcohol).

There is more than fashion at work, however. As I document daily on my Food & Health Skeptic blog, there is a constant flood of absurdities appearing in the medical literature. There needs to be more than fashion behind that. And what is behind it is simply attention-seeking. Every scientist wants to be seen as someone who has "discovered" something. But real discoveries are rare so the slightest hint that a scientist has observed something going on will be trumpeted worldwide. And because real discoveries are rare, any purported discovery will be piled onto by lots of other scientists who want to be in on the glory of having made a contribution to the elucidation of this new phenomenon.

The clearest example of this is the cholesterol and polyunsaturated fats obsession. To cut a long story short, there is NO evidence that a low cholesterol diet lowers the amount of cholesterol in your blood nor is there any evidence that saturated fats in your diet are bad for you. In fact, some studies have shown that people on a diet low in saturated fats die SOONER. I have a research review up -- just above this post -- that sets out in detail the evidence concerned. Yet we are still bombarded with messages about the desirability of a diet low in cholesterol and low in saturated fats. Our supermarkets are full of products that prominently and proudly proclaim that they are "low" in those constituents.

So why have the research findings not got through to the general public? Because scientists themselves ignore research that does not suit them. Let me tell you why:

The "easy" area of medical research is epidemiology: Take a large group of patients. Get reports from them on where they stand on a variety of attributes (e.g. how fat they are or how much fat they eat) and then wait to see who dies. Once you have got a large enough group of dead patients you then look through your files to see if there is something that the dead patients tend to have more of. Very often you find something, as you would on chance alone. Real scientists refer to such a procedure as "data dredging" and discount it but real scientists are a rare breed. Attention-seeking scientists are far more common and it is their reports of such rubbish findings that fill the medical literature.

But such rubbish findings are a godsend to other scientists. They can then put in for big funding to study this new finding. There is a new bandwagon that they can leap onto. But the only really conclusive way of verifying or falsifying the new "finding" is a longditudinal double-blind study -- i.e. you have to get a large and representative group of people and get half of them to change their ways in some respect (e.g. eat less fat). You then wait for years and see which group dies soonest. And at the end of that time what do you find? You typically find that the epidemiological hypothesis is not confirmed. The intervention (change) you have done to people's habits is just as likely to have done harm as good but most often it has done nothing at all. And that is where the cholesterol and saturated fat research has arrived at after all the years during which the "evil fat" gospel has been rammed down people's throats.

So where do you go from there? Do you admit that the theory you have built your career on (and which has delivered to you a cornucopia of research dollars) was all wrong? I think you can guess the answer to that. What you say is: "More research is needed" -- and carry on as before. And the poor old mug taxpayer coughs up more dollars to keep the nonsense alive.

And much the same applies to global warming theory. It initially looked good but, as more and more evidence accumulates, the holes in it get bigger and bigger. You can see that in the IPCC reports. They have progressively scaled down their predictions of what sea-level rise we are to expect. But there is NO WAY that they can admit that the whole thing is a crock so, as the evidence turns against them, they ratchet up the hysteria to keep those research dollars flowing. And it works. "More research is needed" has become the mantra of many politicians too.

But it leaves the average person totally betrayed. Attention-seeking medical scientists have led him towards useless lifestyle changes that may even harm him and attention-seeking climate scientists have led him to support political programs that will certainly impoverish him. So dishonest science is in fact a far greater evil than the rather wacky tribe of kneejerk nature-lovers.

Clinging to disproven theories is also rampant in my own field of academic specialization -- psychology -- but, fortunately, nobody takes much notice of psychologists.

For more on the poor track record of epidemiological "findings", see the sad caution from a medical researcher that I reproduced as part of my post about the latest vitamin D nonsense. Note also another review article on cholesterol and fat myths that I have linked to before.

Revolt against food faddism in Australian schools

MONTHS after state schools were ordered to dump junk food from their menus, most are still serving pizza, hot dogs, ice-cream and other processed foods. The Government introduced the "traffic light system" in its Smart Choices program to tackle childhood obesity on January 1, but half of schools have failed to get the balance right. Pizzas and hot dogs were labelled under the system as "amber" foods - to be served only occasionally - but Queensland Association of School Tuckshops spokeswoman Chris Ogden said schools were lagging. "A few have gone all 'green', but it is much easier to stick a tray of sausage rolls in the oven than make up salad rolls and wraps, that sort of thing," she said. "We can buy in pre-chopped lettuce and carrot but they come at a premium price."

Under the laws, foods are divided into "green" or healthy choices like salads, and "amber" or processed foods including low-fat pies, hot dogs and pizza. "Red" choices are limited to twice a term, which has made staging sausage sizzle fundraisers a nightmare at some schools.

A random survey of more than 100 primary school menus by The Courier-Mail showed very few indicated which choices were amber, green or red. Of the eight menus which were colour-coded, 45 per cent of the offerings were either amber or red. Eagleby South State School, in Logan, even offered daily "meal deals" such as a dagwood dog, juice and packet of chips for $2.70 and a pie, juice, Paddle Pop and packet of chips for $4.

Ms Ogden said although many schools tried hard, it was impossible to stop students from buying restricted foods outside the school grounds. "There's a fast food outlet near every school, whether it's a service station, a supermarket or a KFC or McDonald's," she said.

Responding to reports MacGregor State High School students had eaten 60 McDonald's burgers in one sitting, an Education Queensland spokesman said the students had not been on their lunch break and had had permission from their parents to leave the school.

Quality Food Services, which distributes food to about 800 school tuckshops, said pie sales had dropped under the Smart Choices guidelines because the new low-fat, low-salt varieties were relatively bland. Spokesman Glen Bound said tuckshops could not compete with local shops offering junk food. "It's a big problem at Runcorn State High, where the shop around the corner has changed its menu to suit the students. Their business has gone through the roof," he said. He had heard of students at other schools having pizzas delivered to the fence, and an enterprising student who took a backpack full of soft drink to school to sell to classmates.



Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

Trans fats:

For one summary of the weak science behind the "trans-fat" hysteria, see here. Trans fats have only a temporary effect on blood chemistry and the evidence of lasting harm from them is dubious. By taking extreme groups in trans fats intake, some weak association with coronary heart disease has at times been shown in some sub-populations but extreme group studies are inherently at risk of confounding with other factors and are intrinsically of little interest to the average person.


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